I will quite happily admit to sending low offers all the time, its what the best offer function is for in my opinion.
This could make me a bad person, but I would always send an lower offer through first, even if I was happy for the BIN price. If they don’t accept, fine, i’ll just buy it anyway, and if they do accept great!
We sell an awful lot on eBay, and would expect buyers to do exactly the same back to me!
Just last night, a seller had put online a 2014 Macbook for £250. Incredibly dodgy photos, and nothing to say if it was working. After a few questions, he supplied to proof of purchase, and a screenshot of it actually powered up so I was happy.
I offered £110, and he accepted within seconds.
Does that make me cheap? Maybe….
But he wouldn’t have accepted if he wasn’t happy…